Most of us have played it since we were children and, very soon when Christmas comes around, we could well find ourselves ready to tackle it with the rest of the family once again.

The Monopoly board game is a common staple in most households and, if you or your family play it regularly, it probably comes complete with lots of childhood memories (hopefully, not too many of those involving arguments!)

But it looks like someone has actually taken the time and trouble to read the rules of the game pretty much everyone knows how to play - and discovered a rule which no-one really seems to know about.

Alternatively, those that do know about it just seem to ignore it - because it is pretty game-changing, as the Mirror Online reports.

Did you know about this rule in Monopoly? (Image: Birmingham Mail)

Not least of all because it could actually considerably shorten the amount of time we spend playing it - and perhaps nobody wants to speed up the process on those long days after Christmas.

Basically, according to the rules, if you land on a property and you decide not to buy it, the Banker should then sell it at auction to the highest bidder.

As these tweets explain:

The intriguing part is the question of what properties could end up being sold for - as this will entirely depend on if anyone else bid, driving the price up. If no one bids, then, in theory, a player could get a property for under market value.

Not convinced by the tweets alone? This is what the official rulebook says:

"Whenever you land on an unowned property, you may buy that property from the Bank at its printed price.